SAO PAULO, July 12 (Reuters) - Brazilian development bank BNDES said on Thursday it would suspend an auction of electricity distributors owned by state-controlled utility Centrais Eletricas Brasileiras SA as it evaluates a court ruling blocking the sales.

BNDES, which is overseeing the sales process, will set a new date to auction the six distributors in north and northeastern Brazil once it has legal authorization to do so, following on a ruling by a court in Rio de Janeiro, it said in a statement. The auction had previously been scheduled for July 26.

Eletrobras, as the firm is known, is seeking to offload the heavily indebted distributors ahead of government plans to privatize the overall company.

A Brazil Supreme Court ruled in June that all the privatizations must be approved by Congress to move forward. While the lower house has given approval to privatize the distributors, the Senate is still considering the measure.

Eletrobras representatives did not immediately respond to a request for comment. (Reporting by Luciano Costa; Writing by Jake Spring; Editing by Christian Plumb and Leslie Adler)